Receptor

Patent Pending In biochemistry and pharmacology, a receptor is a protein molecule usually found inside or on the surface of a cell, that receives chemical signals from outside the cell. When such chemical signals bind to a receptor, they cause some form of cellular/tissue response, e.g. change in the electrical activity of the cell. In this sense, a receptor is a protein molecule that recognises and responds to endogenous chemical signals, e.g. the acetylcholine receptor recognised and responds to its endogenous ligand, acetylcholine. However sometimes in pharmacology, the term is also used to include other proteins that are drug targets, such as enzymes, transporters and ion channels.